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So the Dyson Fan is cool. But it has a thrust to weight ration of 0.6. Not very efficient for flight. Its great at sucking large amounts of air but not at a very high velocity. Thrust is small amounts of air at high speed correct me if I'm wrong. Is there any way to get the Dyson Fan to blow air at a faster speed without increasing the size of the fan.

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  • $\begingroup$ Related: Could a Dyson fan scale up to be used as a bladeless aircraft engine? $\endgroup$ – ymb1 May 24 at 18:37
  • $\begingroup$ I saw that but I asked if there was a way to accelerate the air faster using this air foil $\endgroup$ – Useruuu May 24 at 18:43
  • $\begingroup$ What can’t a blow harder do? $\endgroup$ – vasin1987 May 24 at 19:06
  • $\begingroup$ no im trying to see if you can take the force of a jet engine and apply it to this Dyson Fan design. is it possible $\endgroup$ – Useruuu May 24 at 19:16
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Thrust is small amounts of air at high speed correct me if I'm wrong.

No, more air at lower speed is more efficient. Thrust is derivative of momentum added to the air, while power is derivative of kinetic energy added to it. Since momentum grows with velocity, but energy with square of velocity, accelerating more air by less creates the same thrust with less power.

Dyson fan works by blowing a thin stream of high velocity air along the ring, which then pulls in more air to create a very smooth air flow through the ring. To create this high velocity flow, you have to provide a lot of energy, which will then dissipate as heat when the streams mix, but you have no way to recover any of it as it happens already behind the fan. So it is very inefficient and while adding power will make it generate more thrust, it will only further reduce the efficiency as the flow speed increases.

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Yes you can make a Dyson fan blow more air without making it larger - just increase the speed and torque. It will get louder and consume (probably disproportionately) more power.

No this would not be remotely practical as a means of aircraft propulsion. Existing turbofans and propeller designs are highly optimized and pretty much the best tools for the job.

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